


Summertime Vow

by plastics



Category: Original Work
Genre: F/M, Implied/Referenced Abuse, Loss of Virginity, Oral Sex, Sibling Incest, Summer Vacation, Vaginal Sex, threat of getting caught
Language: English
Status: Completed
Published: 2019-09-22
Updated: 2019-09-22
Packaged: 2020-10-25 21:03:36
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,411
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20730725
Author URL: https://archiveofourown.org/users/plastics/pseuds/plastics
Summary: It's never too late to try and get just a little bit closer.





	Summertime Vow

**Author's Note:**

  * For [thecloserkin (tabacoychanel)](https://archiveofourown.org/users/tabacoychanel/gifts).

> Here's a very last-minute treat, hope you enjoy!
> 
> Content note: ages are purposefully ambiguous, but Older Brother is somewhere in the first half of college while Younger Sister is somewhere in the later half of high school, by US measurements.

The sky is a deep indigo by the time Tony gets back to the house. The front door is locked. So’s the back slider. This isn’t particularly surprising, but it sends a flaming lick of rage up his body. It’s exactly the sort of cartoonish shit his parents like to pull, like a night sleeping in his car or in the bungalow will instill enough contrite shame in him to eat up whatever else they feel is fit to feed him.

He thinks long and hard about sending a lawn chair through a window. It’s probably what they want, anyway, right down to him tripping the alarm system and getting picked up for breaking and entering when the cops show up. Their summer home is isolated enough that it’d be a one-sided embarrassment. 

His phone buzzes before he can decide if he’d hate spending the night in jail more than they’d hate having to get him out before it got too public. **Window’s open.**

Tony glances up, and, sure enough, he sees a crack in one of the upstairs windows. A fissure of fondness cracks through the anger.

The house is built obnoxiously enough that it’s not actually that difficult to scale, and the window slides open easily. He has to climb over a desk, but a path had been cleared for him onto the floor. He’d been in the dark long enough that he can still make out the form curled up on the bed—upright, long dark hair piled on top of her head, arms holding in foalish legs, chin resting on knees, ankles crossed.

“Hey,” Tony says. 

Leigh hushes him, quick and nervous. Their parents’ room was on the other side of the wall. Tony can imagine the things they said after he left and it bubbles up another round of anger, but it’s hard to hold onto with just Leigh left in front of him.

He feels his voice lowering, gentling, as he says, “I got your allergy meds.”

It stings a little, the surprise in her voice when Leigh responds, _ “Oh. _ I thought—I mean, thank you, but you didn’t need to. It was just a headache, honestly.”

“Yeah, well, homeopathic mushroom pills aren’t going to help,” Tony scoffs. He tosses the bottle onto the bed and flinches in sympathy when Leigh jolts when it lands near her.

They used to be close, is the thing. Can’t even blame it all on Mom and Dad playing favorites; he’d been sick of his own bullshit by the time he got sent off St. Jude’s—juvie for the sons of families too proud to have a son in juvie—and when he got back the next summer, it was like the same wall Leigh built around everyone else and sprung up between them, too. Most of the time, Tony can tell himself he’s used to it, or that it’s fine. It’s been years now. Leigh had been a girl then, but she’s close enough to an adult now that Tony can clearly see where they deviate—how _ good _she is. 

But that’s just most of the time. Right now, he feels drenched in it, embarrassed by the scene earlier, how she must see him if a bottle of over-the-counter meds is a surprising gift. 

Tony should probably just leave her to it. That’s how things work best in this family. His summer will be over soon, anyway, and in a few more years, there won’t be any more summers. But no one has ever accused Tony of being selfless. 

Carefully, he sits at the edge of Leigh’s bed. “We’ve, uh, really had some memories in this place, huh?”

“I guess,” Leigh mumbles. Her cuticles seem to be holding most of her attention.

“Like, um,” Tony says. “When we first got the house, and Dad was still tearing the whole thing apart like he knew a thing about interior design, so we’d spend the whole day out, like, trying to catch frogs and forcing them into arranged marriages?”

Finally, Leigh lets out a low snort that’s mostly like laughter. “Yeah, except you hated actually touching them. Always made me do it.”

“Well, you’re welcome, Miss Exceptional Scientific Performance,” Tony says. 

Leigh makes a dismissive noise—“All those end-of-year awards are bullshit.”—but it’s enough to start the first conversation they’ve had in, god, too long. Tony slots himself next to her on the bed. Up close, he can tell the t-shirt she’s wearing is actually one of his from a soccer camp he took part in years ago. He hadn’t even thought to look for it since then, but seeing it now, on her, fills him with a heavy feeling he can’t quite put a name to. Something like loss.

“Why did we stop doing this?” Tony blurts out. “Like, we’ve both _ been _here.”

“I mean, you spend most of the time going after other lake girls.”

‘No, I don’t,” Tony responds automatically, but it’s a hollow denial. The best part of being trapped with his family has always been getting away from his family. Even when he struck out with those girls, there was… he wishes there was something less douchey to call it than _ the thrill of the chase, _ but he thinks that the girls have fun too, luring him and his buddies to their parties or family boats, sharing their drugs, doing things that don’t really count because it’s just the lake—odds are they’ll never see each other again, and if they do, it’ll only be a few weeks at a time at the lake once more.

Still, there’s something like a heavy blanket of embarrassment covering him at the thought of _ Leigh _seeing him act like that. “You could have come with,” Tony offers, although he knows he would have hated it. Doesn’t trust his friends like that.

Leigh makes an equally dismissive noise. The night’s quiet before starts speaking again, staggered, “I’m not like you. Or them. I’m just… I don’t know. Boring. Ugly.”

“You’re _ not _ ugly,” Tony protests, incredulous. She’s always been pinned up tight, sure, but Tony’s always seen it as a side effect of being Mom Jr., only at least Leigh actually seemed content when she was left alone to do her own thing. It’s not like Tony _ wanted _to exclude her. “You really could have. It’s not like a secret club, you can just show up. Do shit.”

“Okay, but you have to have _ done shit _ before. It’s, like, painfully obvious I haven’t. Ever. No one’s even kissed me before,” Leigh admits with barely more than a breath. Tony can hardly believe. It’s not something he’s really thought of, not at length, but even watching from a distance, Leigh’s beautiful. Of course she is. Even going to that all-girls school, it’s not like she has _ no _friends, and there have been dances, summer camps—

“Somebody’s wanted to. I can promise you that,” Tony says. 

“No, they haven’t.”

_ “Yes, _they have.”

“I think I’d know my own fucking life, Easton!” Her voice spikes above even her normal speaking voice, and Tony shushes her even as he cringes at his name. It was something he’d shed around the same time he learned what a compass was—before he’d hit his growth spurt, people used to ask if he and Leigh were twins, and that’d embarrassed him deeply, too.

“Alright, fine. That’s fine. It’s not, like, that weird. You know Jack, right? If you believed anything out of that kid’s mouth, you’d think he was killing shit daily, and I swear to God he hasn’t gotten any since—well.” Tony’s mouth snaps shut, jaw clenching. He doesn’t want to talk about guys like Jack Barnum with his sister. And what the fuck is he saying, that Leigh should offer herself to those types of assholes to gain access to some sort of fantasy teen summer at the lake? It’s not worth it. Leigh remembers looking out, Tony remembers sunburns and bug bites from long days spent outside until Dad drunk himself to back to bed, bad sex with girls who talked like porn stars because they thought it’d turn him on but didn’t want to look him in the eye.

He should tell her that it’s not worth it. Guys her age aren’t worth it. Guys _ Tony’s _age aren’t worth it. Instead, Tony stares at the rapid rising of her chest, the glassy sheen over blue eyes.

Tony isn’t a good brother. He hasn’t been there for Leigh a lot, even when could have been. He’s angry and selfish and impulsive. He says, “I mean, if you really… I mean _ seriously—” _

“What?” Leigh asks, but Tony’s shame won’t let him finish the thought. He wants to climb right back out that window and not stop until he hits San Diego. End this whole little misguided attempt at family time. But it’s just like himself when that shame drifts off into the night instead as soon as Leigh continues, “Like, practice or something?”

“Sure,” Tony says, and now he’s the one whose voice can’t rise above the barest whisper, even as he watches Leigh turn more fully towards him. 

A few tears had escaped, but she wipes them away before she says, “I mean, it’s not like it’d really count, right? It’s just… us. We know each other already. It couldn’t be that much more.”

“Exactly,” Tony says. He’s fairly sure he’s committing to multiple felonies, but it wouldn’t be the first time. Wouldn’t be the first time _ here, _ like it’s all the lake is good for. And Leigh’s smart. Even if she’s inexperienced, she’s not naive. Tony isn’t doing anything but giving his little sister what she wants. That’s all _ Tony _wants.

The lie evaporates from Tony’s head the second he has to reach out for Leigh. Her hip fits so perfectly beneath his hand, but her lips are better, soft and flush against his own. It shouldn’t feel so natural for them to be drawn together, but it does, feels perfect for her arms to twine around his neck as their bodies press together. When a gasp lets Tony lick into her mouth, she tastes of mint.

He fists his hands in her shirt—his shirt—and breaks away, just far enough for his eyes to be able to focus on Leigh in the dim light. It should be like a bucket of cold water, remembering that this is his _ sister _he’s making out with and not some random chick, but it’s not. It doesn’t. Her thighs clench when his hand drifts down and grazes the bare skin there. She’s wearing shorts but they’re hiked up high. When he curls his hand just below her ass, he can feel the heat radiating off of her.

His dick is hard. Tony can feel his mind narrowing in, how badly he wants, so much more than he can or should take. But it’s not about him. He can’t believe that no one’s touched Leigh before this, that she’s trusting _ him, _ after all the shit he’s pulled today and the rest of their lives. When he lets his hand drift high and pets at the core of her so gently through two layers of pure cotton, she shivers so beautifully.

“What do you want?” Tony asks.

“I don’t know,” Leigh responds, voice high even in a whisper as her hips twitch to press down against Tony’s fingers. God, he wants to give her everything. He leans back in and kisses the hollow of her throat, then begins to work his way down. His blood boils as he goes to ease down the waistband of her shorts—sets him on fire when she kicks off her panties in one go.

Tony keeps one of her thighs aside in his hand. The sight of her makes it hard to breathe even in just the dim light of the mood. A loud, unreasonable piece of him wishes they were doing this in broad daylight, or that he could take his phone out, flash on. 

It’s a selfish instinct, really, that has him leaning in and saying, “Any guy who doesn’t do this isn’t worth your time, alright?”

Leigh makes a vague, agreeable noise. Tony can hear her breathing harder even as the spread of her legs, her pussy takes up his vision. When he sticks out his tongue and licks up her slit, he’s the first person to have touched her there, tasted her, made her gasp quite like that. He makes it good, too, teasing at her clit then sucking on it hard enough she has to shove her hand into her mouth. He wants to be the best she’ll ever get, too, the benchmark no one else will ever live up to. 

It’s not fair. It’s not what she asked for. But it’s what Tony wants to give.

When Leigh comes, her whole body rolls with it, shaking in aftershocks as Tony slowly, reluctantly draws back. He doesn’t get far before she makes a frustrated noise and shoves her free hand downward, hooking two fingers into herself and pressing deep, wrist jerking hard. The image is a shock—has Tony’s cock drooling where it’s still trapped tight in his shorts.

“Please,” Leigh says, then when Tony’s hand drifts up to meet hers, she snaps, _ “No.” _

His mind is blank for a long moment, not even daring to comprehend what she’s asking for until it’s all he can imagine. Tony should leave. He went too far when he lay down with her. Eating her out was unforgivable. But this, this would be—

All he can say is, _ “Babe.” _

“Please,” she repeats. “I want it so bad. Want you.”

Tony can’t say no to her. Of course he can’t. He doesn’t even want to, not at all, not really, and he’s not a good enough person to deny her just so he can wake up the next morning a slightly better person than he actually is.

He is just barely good enough to say, “Condoms. We need—”

“I have some in my bag,” Leigh interrupts, and at the look Tony gives her, she shifts uncomfortably. “What? A girl can hope.”

“Uh huh. And you’re sure they’re not expired?”

The condoms were, in fact, previously stolen from Tony, which means they’re both the right size and not terribly old. It’s another thing to feed to the greedy monster inside him—everything circling back to Tony like they’re caught too close to a black hole. It’s for the best, though. He knows he wouldn’t have needed much of an excuse to feel that wet clutch on his bare cock.

But he’s not going to do that. He’s going to teach his sister safe sex practices, and then he’s going to fuck her as good as she’ll ever get fucked.

Crawling back between Leigh’s legs and into her arms feels like perfection. They fit together so well, even as Leigh gasps and whines as Tony works his dick into her. This is probably the most patient he’s ever been about it, and she’s still acting he’s reconstructing the world around them. He watches, rapt, as her face contorts and relaxes, pain and pleasure.

Tony pushes her shirt up and, fuck, even her tits are perfect, rosy nipples hard at their center. He can’t help but lean down and take one in his mouth, both of them shuddering as she clenches down on him.

“Fuck, E,” Leigh gasps, and surely he’s heard her swear before, but he can’t get over it, what he’s doing to her, how nobody but him knows what wound-tight perfect little sister is like when you pull at her strings.

His best fuck ever ambitions might have been a little high; Tony underestimated how much it’d affect _ him, _ and faster than he’d like he can feel his thrusts getting sloppy, eager as tension pools in his stomach ready to release. He has to stop at one point, mouth frantic on her chest and collarbones, praying the intensity will dim.

“Can I… Can I—” and she doesn’t finish the thought but she’s pushing at his shoulder, so he goes. 

It feels truly awful for his cock to fully withdraw and then truly amazing to have her straddle him. He can’t get over how lovely she looks in the moonlight, even as her face loses the timid, uncertain cast she always has it in. Her eyes are on fire as she reaches down and aligns his cock back up against where her folds split, thighs flexing as she finds her own rhythm. 

Tony knew that Leigh jogs and does cross-country stuff, but he apparently underestimated how _ strong _it’d made her recently. Her bed frame rattles as she rides him, hard, her eyes closed as she moans lowly, the hand not bracing on Tony’s stomach working just as hard on her clit, nothing left for him to do but hold on and chant, "God, baby, you're so good, so beautiful, holy fuck, please, please."

They’re kind of loud, Tony is realizing. It takes longer than it should for him to piece together why that matters, even as the subtle sound of the frame knocking against the wall echoes in his ears. “Wee, you gotta be quiet, Mom and Dad—”

“Fuck Mom and Dad,” Leigh snaps, and, embarrassingly, that is when Tony comes, as hard as ever had. He groans through gritted teeth, barrelling towards oversensitive as he feels Leigh freeze and flutter tight around him in a perfect moment.

When Leigh finally shifts off of him, Tony pulls off the condom and knots it with numb hands. He tosses it in the vague direction of the trash can. Either she can get in the morning or the cleaning staff will, and they’re no stranger to discretion.

Tony should go back to his room. Or, really, he should sneak back out and find a couch to crash on for a few days. Instead, he collapses back into Leigh’s bed and savors the feeling of her curling up next to him. He thinks this is as close as they’ve been in years. Maybe Leigh was right about him being too far gone for her to reach, before. Maybe things could be different. Not like this, not all the time, but something to hold onto when they’re both out of the house for good.

“So, uh,” Tony starts. “What are you doing for the rest of summer? Maybe I could show you around SD or something. Give you another chance to stretch your wings or whatever.”

“... Maybe. I’m, uh, touring colleges, mostly. Or that’s the plan, at least,” Leigh responds.

“Oh, yeah, totally, cool. I remember that. Or, well, I went to one and committed a bunch of my buddies were touring everywhere,” Tony says, and he’s babbling, since when does he babble? “Where are you looking?”

Leigh swallows. She says, “Mom and I are going to take a trip to Massachusetts before school starts up. See a couple of the liberal arts schools up there.”

“What, you’re too good for Claremont? Or even, fuck, that one school in Washington. Gonzaga.” It’s not really a surprise; colleges all over the country sponge up the excess of unremarkable, spoiled rich kids Californian private schools crank out. Leigh _ is _remarkable, though, and it’s harder to get much farther away than Mass. That thought hurts, suddenly. 

Tony regrets saying anything when he feels her cringe away from his side.

“I’m sorry,” she responds in a quiet exhale.

“No, Westleigh, stop. I shouldn’t—whatever you want. Seriously.” It’ll be good for her to get away from their parents, Tony thinks. From him. Let her be the normal one. He tells himself this over and over, trying to convince himself and swallow down the choking feeling in his throat.

Eventually, Leigh squirms and whispers, like she can take it back if Tony fights it, “You should go to bed.”

“Yeah,” he says instead. Tony slides out of her bed and pulls his clothes back into place. They stick uncomfortably. He needs a shower, or ten, although he’s pretty sure it won’t wash the worst of it away. He feels even more drained than he usually does after a fight or a fuck. When he glances back at Leigh and sees her watching him, eyes too wide to be close to sleep, it just hurts.

“G’night, Eater.”

“Sleep tight, Wheaties,” Tony responds, and then he closes the door behind.


End file.
